Jtekt Corporation

Toyoda Koki Kabushiki Kaisha

Tsutomu Matsumoto

Atsuo Sakai

Tomohiro Nozu

Yutaka Mori

Kunihiko Eto

Tomoaki Kato

Jiro Nakano

Kazumasa Kodama

Kenichi Abe

Kenichi Kozuka

Shigeo Tanooka

Shotaro Niimi

Akiyoshi Kakita

Shigeo Iwashita

Tetsuya Yamazaki

Kiyotaka Kato

Shiro Takeuchi

Kenta Taniguchi

Kazuya Sakai

Kazushi Suzuki

Takehide Adachi

Yuta Takeuchi

Takayoshi Suzuki

Tsuguhiro Somekawa

Kyousuke Haga

Masahiro Hayakawa

A drive force transmission apparatus is mountable on a four-wheel drive vehicle switchable between a four-wheel drive mode that transmits a drive force of an engine to front wheels and rear wheels, and a two-wheel drive mode that transmits the drive force to only the front wheels. The drive force transmission apparatus allows adjustment of the drive force to the rear wheels, and includes a multi-plate clutch, a piston for axially pressing the multi-plate clutch, an actuator for axially moving the piston, and a control unit for controlling the actuator. Upon satisfaction of a predetermined condition that indicates a high probability of the vehicle needing to be switched from the two-wheel drive mode to the four-wheel drive mode, the control unit causes the actuator to displace the piston by a predetermined amount with respect to an initial position of the piston toward the multi-plate clutch.

Drive force transmission apparatus

In a four-wheel-drive vehicle, a hydraulic unit has an electric motor, to which a motor current is supplied from a control device, and a pump that is actuated by rotation of a motor shaft, and a drive force transfer device has a piston that is moved by the pressure of working oil discharged from the pump, and a friction clutch that is switchable between a transfer state and a blocked state, in which transfer of a drive force to rear wheels is allowed and blocked, respectively, in accordance with movement of the piston. The control device detects the presence or absence of an abnormality of a flow passage forming member, which forms a flow passage for working oil, in accordance with at least any of a motor current and the number of revolutions of a motor shaft at the time when the motor shaft is rotated by applying a voltage to the electric motor.

Four-wheel-drive vehicle

A clutch apparatus includes a clutch hub, a clutch drum, a multi-plate clutch having inner clutch plates and outer clutch plates, a piston for pressing the multi-plate clutch, an electric motor, a moving mechanism for moving the piston in an axial direction in accordance with the amount of rotation of the electric motor, and a control unit for controlling the electric motor. When increasing a rotational force that is transmitted between the clutch hub and the clutch drum by increasing electric current that is supplied to the electric motor, the control unit moves the piston in the axial direction by temporarily supplying the electric motor with the electric current having a first current value that is greater than a second current value corresponding to a target rotational force that needs to be transmitted between the clutch hub and the clutch drum.

Clutch apparatus and method for controlling the clutch apparatus

A control device for an electromagnetic clutch includes: a first switch that is connected to one end of an electromagnetic coil forming the electromagnetic clutch; a second switch that is connected to the other end of the electromagnetic coil; and a microcomputer that controls an on/off state of both switches. The control device further includes: a first diode having its anode terminal connected between the electromagnetic coil and the first switch and its cathode terminal connected between the second switch and an in-vehicle power source; and a second diode having its anode terminal connected to the ground and its cathode terminal connected between the electromagnetic coil and the second switch. The microcomputer stops power supply to the electromagnetic coil by turning off both switches.

Control device for electromagnetic clutch

A rotation angle sensor outputs detection signals based on a rotation angle of a rotary shaft. The detection signals that are output from the rotation angle sensor include first to fourth detection signals that sinusoidally change with the rotation angle of the rotary shaft and that are different in phase from one another. Here, a phase difference between the first detection signal and the second detection signal and a phase difference between the third detection signal and the fourth detection signal are each set to 90&#xb0;. In addition, a phase difference between the first detection signal and the third detection signal and a phase difference between the second detection signal and the fourth detection signal are each set to 45&#xb0;.

Rotation angle sensor

There is provided an actuator control apparatus configured such that even when an electronic device that generates an electric signal to be used to control an actuator is provided in the form of a duplexed system, an increase in the number of communication paths between the electronic device and a controller is suppressed. A torque sensor and a rotation angle sensor are each provided in the form of a duplexed system. Two sets of a torque sensor and a rotation angle sensor are connected to a microcomputer via a SPI communication line. The torque sensors and the rotation angle sensors are connected to the microcomputer via CS communication lines, respectively. By selecting a communication target via a corresponding one of the CS communication lines, the microcomputer is able to receive multiple kinds of electric signals via each one of the SPI communication lines.

Actuator control apparatus

A motor control device with which both high-accuracy current detection and improvement in voltage utilization factor are achieved is provided. When an ON time of any one of low potential side switching elements corresponding to respective phases in a driving circuit is shorter than a detection time of a current value, a microcomputer estimates a phase current value of a current undetectable phase based on current values of two phases other than the current undetectable phase corresponding to the said FET. Then, at the time of current detection using the blind correction, during current detection for two phases, other than the current undetectable phase, based on which the blind correction is performed, motor control signals for maintaining switching states of a switching arm corresponding to the current undetectable phase are output.

Motor control device and electric power steering system

According to the breaking detection processing, it is determined that (A) iu of AC current (absolute value) supplied to a motor is less than 0.5 amperes or iv thereof is less 0.5 amperes or iw thereof is less than 0.5 amperes, (B) the angular velocity of the motor is 1 rad/s or more and (C) at least any one of the current instruction values id*, iq* is 5 amperes or more in a step and then, a period in which all these three conditions (A)&#x2013;(C) are satisfied at the same time is determined in another step. Consequently, it is determined that any one of the power supply lines in the motor is broken and a breaking detection flag is set to ON so as to detect the breaking.

Motor power supply line breaking detection method, motor control apparatus and electric power steering mechanism using the same and computer program thereof

An angle detection device that accurately detects a rotational angle even if the ratio of an detection voltage relative to an excitation voltage of a resolver fluctuates. The angle detection device includes an angle detector and a controller connected to the angle detector. The angle detector includes an excitation coil, which is arranged on a predetermined rotary shaft and supplied with excitation voltage, and a pair of detection coils. Each detection coil is arranged near the excitation coil to induce detection voltage when excitation voltage excites the excitation coil. The detection voltages of the detection coils have different phases. A controller calculates the rotational angle of the excitation coil with the detection voltages induced to the detection coils. Further, the controller includes a correction unit for correcting the amplitude of the excitation voltage to maintain each of the induced detection voltages at a predetermined value.

Angle detection device and torque sensor incorporating angle detection device

An electric power steering apparatus comprises an input shaft transmitting a rotation from a steering wheel and an output shaft rotatably connected to the input shaft through a torsion bar relative to the input shaft. A drive motor is coaxially arranged relative to both of the input shaft and the output shaft. A reduction mechanism coaxially provided in a housing relative to the input and output shaft transmits a rotation of the drive motor to the output shaft so as to reduce the rotation of the drive motor at a constant reduction rate. A torque sensor detects a torque added to the torsion bar as a relative rotational displacement between the input shaft and the output shaft. The drive motor is rotationally controlled in accordance with the detected torque by the torque sensor.

Motor-driven power steering apparatus

There is disclosed a device for controlling steering force in a power steering apparatus having an electromagnetic control valve according to road and driving conditions. The device includes a car speed sensor, a steering angle sensor, first arithmetic means, second arithmetic means, correcting means, control current arithmetic means and controlling means. The first arithmetic means computes a driving condition index by using car speed information. The second arithmetic means computes a road condition index by using steering angle signals. The correcting means converts the driving condition index into a correction driving condition index which takes any one of several stepwise-varied values. The control current arithmetic means computes an output control current value applied to electromagnetic control valve by the controlling means. The device further includes means for detecting lateral acceleration utilized for controlling the steering force.

Device for controlling steering force in power steering apparatus

A steering characteristic controller for a power steering system of the type that an actuator operable in response to an electric current thereto varies the characteristic of a assisting power generated by a power steering gear. The controller includes a signal converter responsive to a signal from a vehicle speed sensor for converting the vehicle speed signal into a voltage signal corresponding thereto and a drive circuit connected to the actuator for driving the same in response to the voltage signal from the signal converter. The controller further includes a gain adjuster, which varies the output gain of the voltage signal from the signal converter in correspondence to the magnitude of a signal from a vehicle load sensor.

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Anjo, Japan

Tsutomu Matsumoto